Centenial vs Biennial - What's the difference?

As an adjective biennial is

happening every two years.

As a noun biennial is

a plant that requires two years to complete its life-cycle, germinating and growing in its first year, then producing its flowers and fruit in its second year, after which it usually dies.

centenial

Not English

Centenial has no English definition. It may be misspelled.

English words similar to 'centenial':

centennial, continual, cantonal, continuall, centinel, contentful, conational

biennial

English

Adjective

(-)

Happening every two years.

Lasting for two years.

Noun

(en noun)

A plant that requires two years to complete its life-cycle, germinating and growing in its first year, then producing its flowers and fruit in its second year, after which it usually dies.